It's sequenced. I used Sonar Music Creator 2005 (I love its Amiga-like staff view), and the piano virtual instrument I've been using for what feels like forever. I wrote it (like all of my piano stuff these days) on two tracks; one for the left hand, and one for the right (keeps the whole "third hand" thing away most of the time ?). I played with the velocity and the tempo a lot in the program, trying to capture what I was picturing in my head as I listened to what I'd written as I went along; giving it tempo changes in areas where I believed they would feel good/natural. I've also tinkered with the EQing for the piano over the years, to try and make it sound a bit nicer to my ears (it's harsh sounding without the EQing), So yeah, it's not me performing it. It's just me trying my best to make it feel performed.
And thanks for the compliments, djp. Scary to think it's been nineteen and a half years since my Darius remix was posted, huh?